The thousands of predominantly Central American migrants who have died or gone missing on the journey to the USA are among 56,800 people-including refugees and asylum seekers-worldwide who have died or disappeared since 2014, the AP has found in a separate report.

Choosing a spot at dusk where the fence was lower, just over a quarter mile from the Pacific, eventually roughly two dozen people had gone over. All surrendered to border patrol agents who arrived on the scene.

At least two "caravans" started out from El Salvador and Honduras in late October, storming the gates on the border bridge between Guatemala and Mexico.

Mexican officials are shutting down a migrant shelter in Tijuana, and moving members of the caravan further away from the border.

As the situation in Tijuana, Mexico continues to deteriorate as thousands of illegal aliens wait to gain access to the United States, the crisis continues along many different sectors of the border.

The sight of them climbing the fence encouraged others, even as a helicopter patrolled overhead on the United States side. Officials said the migrants were part of a family unit that included three children - a two-year-old, a seven-year-old, and a ten-year-old.

Ninety minutes later, she and her family were over the fence.

The suspect who helped the children over the border wall to the group did not cross into the U.S., CPB said, according to Yuma's KYMA-TV.

Some of the people seek economic opportunity but many tell of death threats. The three migrants were then taken into custody. They hope to still get asylum in the U.S., due to to a court challenge to President Donald Trump's new policy.

The Pentagon said US Defense Secretary Jim Mattis had approved a request to extend the deployment of troops to the US border with Mexico till the end of January.

The attempt to cross into the United States illegally came just days after the migrants were transferred from one temporary shelter to another after it had become unsanitary. "Stand on my head!" one migrant said, egging his companion on.

One child and his mother got over the fence and ran up the hill behind. Mexican authorities arrested and deported those they considered responsible for compromising the city's commitment to public order.